The present invention relates to a core making machine and, more particularly, to a core making machine for making a hollow core from green sand.
In order to facilitate the management of the molding sand and post-treatment of the casting mold, as well as the repeated use of the molding sand, the core in a casting mold is preferably made from the same type of molding sand as that used for making the mold, i.e. green sand. Various attempts to make a core from green sand have encountered difficulty due to inferior fluidity and filling property inherent in the green sand. In addition, the core made from green sand does not show good collapsibility after pouring of molten metal and small permeability to gas. For these reasons, the core making from green sand has not been put into practical use, nor the machines for making core from green sand has been developed yet.